Abstract

Optical Micro Bubble Resonators (OMBR) are emerging as new type of sensors characterized by high Q-factor and embedded micro-fluidic. Sensitivity is related to cavity field penetration and, therefore, to the resonator thickness. At the state of the art, methods for OMBR’s wall thickness evaluation rely only on a theoretical approach. The purpose of this study is to create a non-destructive method for measuring the shell thickness of a microbubble using reflectance confocal microscopy. The method was validated through measurements on etched capillaries with different thickness and finally it was applied on microbubble resonators.

© 2015 Optical Society of America

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References

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    [Crossref]
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    [Crossref]
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2015 (1)

T. H. Besseling, J. Jose, and A. Van Blaaderen, “Methods to calibrate and scale axial distances in confocal microscopy as a function of refractive index,” J. Microsc. 257(2), 142–150 (2015).
[Crossref] [PubMed]

2014 (3)

X. Zhang, L. Liu, and L. Xu, “Ultralow sensing limit in optofluidic micro-bottle resonator biosensor by selfreferenced differential-mode detection scheme,” Appl. Phys. Lett. 104(3), 033703 (2014).
[Crossref]

D. Farnesi, A. Barucci, G. C. Righini, S. Berneschi, S. Soria, and G. Nunzi Conti, “Optical Frequency Conversion in Silica-Whispering-Gallery-Mode Microspherical Resonators,” Phys. Rev. Lett. 112(9), 093901 (2014).
[Crossref] [PubMed]

Y. Yang, J. Ward, and S. N. Chormaic, “Quasi-droplet microbubbles for high resolution sensing applications,” Opt. Express 22(6), 6881–6898 (2014).
[Crossref] [PubMed]

2013 (1)

2011 (3)

2010 (2)

2008 (1)

X. Fan, I. M. White, S. I. Shopova, H. Zhu, J. D. Suter, and Y. Sun, “Sensitive optical biosensors for unlabeled targets: A review,” Anal. Chim. Acta 620(1-2), 8–26 (2008).
[Crossref] [PubMed]

2006 (1)

2001 (1)

G. Cox and C. J. R. Sheppard, “Measurement of thin coatings in the confocal microscope,” Micron 32(7), 701–705 (2001).
[Crossref] [PubMed]

2000 (1)

1996 (1)

1995 (1)

H. Jacobsen and S. Hell, “Effect of the specimen refractive index on the imaging of a confocal fluorescence microscope employing high aperture oil immersion lenses,” Bioimaging 3(1), 39–47 (1995).
[Crossref]

1994 (1)

1987 (1)

Aguilar, J. F.

Barucci, A.

D. Farnesi, A. Barucci, G. C. Righini, S. Berneschi, S. Soria, and G. Nunzi Conti, “Optical Frequency Conversion in Silica-Whispering-Gallery-Mode Microspherical Resonators,” Phys. Rev. Lett. 112(9), 093901 (2014).
[Crossref] [PubMed]

Benson, O.

Berneschi, S.

D. Farnesi, A. Barucci, G. C. Righini, S. Berneschi, S. Soria, and G. Nunzi Conti, “Optical Frequency Conversion in Silica-Whispering-Gallery-Mode Microspherical Resonators,” Phys. Rev. Lett. 112(9), 093901 (2014).
[Crossref] [PubMed]

S. Berneschi, D. Farnesi, F. Cosi, G. N. Conti, S. Pelli, G. C. Righini, and S. Soria, “High Q silica microbubble resonators fabricated by arc discharge,” Opt. Lett. 36(17), 3521–3523 (2011).
[Crossref] [PubMed]

Besseling, T. H.

T. H. Besseling, J. Jose, and A. Van Blaaderen, “Methods to calibrate and scale axial distances in confocal microscopy as a function of refractive index,” J. Microsc. 257(2), 142–150 (2015).
[Crossref] [PubMed]

Boseck, S.

Brady, G. R.

Briggs, A.

Chormaic, S. N.

Y. Yang, J. Ward, and S. N. Chormaic, “Quasi-droplet microbubbles for high resolution sensing applications,” Opt. Express 22(6), 6881–6898 (2014).
[Crossref] [PubMed]

J. Ward, Y. Yang, R. Madugani, and S. N. Chormaic, “Sensing and optomechanics using whispering gallery microbubble resonators,” in Photonics Conference (IPC), (IEEE, 2013), pp. 452–453.
[Crossref]

Cogswell, C. J.

Connolly, T. J.

Conti, G. N.

Cosi, F.

Cox, G.

G. Cox and C. J. R. Sheppard, “Measurement of thin coatings in the confocal microscope,” Micron 32(7), 701–705 (2001).
[Crossref] [PubMed]

Dulashko, Y.

Fan, X.

W. Lee, Y. Sun, H. Li, K. Reddy, M. Sumetsky, and X. Fan, “A quasi-droplet optofluidic ring resonator laser using a micro-bubble,” Appl. Phys. Lett. 99(9), 091102 (2011).
[Crossref]

H. Li, Y. Guo, Y. Sun, K. Reddy, and X. Fan, “Analysis of single nanoparticle detection by using 3-dimensionally confined optofluidic ring resonators,” Opt. Express 18(24), 25081–25088 (2010).
[Crossref] [PubMed]

X. Fan, I. M. White, S. I. Shopova, H. Zhu, J. D. Suter, and Y. Sun, “Sensitive optical biosensors for unlabeled targets: A review,” Anal. Chim. Acta 620(1-2), 8–26 (2008).
[Crossref] [PubMed]

Farnesi, D.

D. Farnesi, A. Barucci, G. C. Righini, S. Berneschi, S. Soria, and G. Nunzi Conti, “Optical Frequency Conversion in Silica-Whispering-Gallery-Mode Microspherical Resonators,” Phys. Rev. Lett. 112(9), 093901 (2014).
[Crossref] [PubMed]

S. Berneschi, D. Farnesi, F. Cosi, G. N. Conti, S. Pelli, G. C. Righini, and S. Soria, “High Q silica microbubble resonators fabricated by arc discharge,” Opt. Lett. 36(17), 3521–3523 (2011).
[Crossref] [PubMed]

Fienup, J. R.

Guo, Y.

Hell, S.

H. Jacobsen and S. Hell, “Effect of the specimen refractive index on the imaging of a confocal fluorescence microscope employing high aperture oil immersion lenses,” Bioimaging 3(1), 39–47 (1995).
[Crossref]

Henze, R.

Jacobsen, H.

H. Jacobsen and S. Hell, “Effect of the specimen refractive index on the imaging of a confocal fluorescence microscope employing high aperture oil immersion lenses,” Bioimaging 3(1), 39–47 (1995).
[Crossref]

Jose, J.

T. H. Besseling, J. Jose, and A. Van Blaaderen, “Methods to calibrate and scale axial distances in confocal microscopy as a function of refractive index,” J. Microsc. 257(2), 142–150 (2015).
[Crossref] [PubMed]

Lee, J.

Lee, W.

W. Lee, Y. Sun, H. Li, K. Reddy, M. Sumetsky, and X. Fan, “A quasi-droplet optofluidic ring resonator laser using a micro-bubble,” Appl. Phys. Lett. 99(9), 091102 (2011).
[Crossref]

Lera, M.

Li, H.

W. Lee, Y. Sun, H. Li, K. Reddy, M. Sumetsky, and X. Fan, “A quasi-droplet optofluidic ring resonator laser using a micro-bubble,” Appl. Phys. Lett. 99(9), 091102 (2011).
[Crossref]

H. Li, Y. Guo, Y. Sun, K. Reddy, and X. Fan, “Analysis of single nanoparticle detection by using 3-dimensionally confined optofluidic ring resonators,” Opt. Express 18(24), 25081–25088 (2010).
[Crossref] [PubMed]

Li, M.

Liu, L.

X. Zhang, L. Liu, and L. Xu, “Ultralow sensing limit in optofluidic micro-bottle resonator biosensor by selfreferenced differential-mode detection scheme,” Appl. Phys. Lett. 104(3), 033703 (2014).
[Crossref]

M. Li, X. Wu, L. Liu, and L. Xu, “Kerr parametric oscillations and frequency comb generation from dispersion compensated silica micro-bubble resonators,” Opt. Express 21(14), 16908–16913 (2013).
[PubMed]

Madugani, R.

J. Ward, Y. Yang, R. Madugani, and S. N. Chormaic, “Sensing and optomechanics using whispering gallery microbubble resonators,” in Photonics Conference (IPC), (IEEE, 2013), pp. 452–453.
[Crossref]

Matthews, H. J.

Nunzi Conti, G.

D. Farnesi, A. Barucci, G. C. Righini, S. Berneschi, S. Soria, and G. Nunzi Conti, “Optical Frequency Conversion in Silica-Whispering-Gallery-Mode Microspherical Resonators,” Phys. Rev. Lett. 112(9), 093901 (2014).
[Crossref] [PubMed]

Pelli, S.

Reddy, K.

W. Lee, Y. Sun, H. Li, K. Reddy, M. Sumetsky, and X. Fan, “A quasi-droplet optofluidic ring resonator laser using a micro-bubble,” Appl. Phys. Lett. 99(9), 091102 (2011).
[Crossref]

H. Li, Y. Guo, Y. Sun, K. Reddy, and X. Fan, “Analysis of single nanoparticle detection by using 3-dimensionally confined optofluidic ring resonators,” Opt. Express 18(24), 25081–25088 (2010).
[Crossref] [PubMed]

Righini, G. C.

D. Farnesi, A. Barucci, G. C. Righini, S. Berneschi, S. Soria, and G. Nunzi Conti, “Optical Frequency Conversion in Silica-Whispering-Gallery-Mode Microspherical Resonators,” Phys. Rev. Lett. 112(9), 093901 (2014).
[Crossref] [PubMed]

S. Berneschi, D. Farnesi, F. Cosi, G. N. Conti, S. Pelli, G. C. Righini, and S. Soria, “High Q silica microbubble resonators fabricated by arc discharge,” Opt. Lett. 36(17), 3521–3523 (2011).
[Crossref] [PubMed]

Seifert, T.

Sheppard, C. J. R.

Shopova, S. I.

X. Fan, I. M. White, S. I. Shopova, H. Zhu, J. D. Suter, and Y. Sun, “Sensitive optical biosensors for unlabeled targets: A review,” Anal. Chim. Acta 620(1-2), 8–26 (2008).
[Crossref] [PubMed]

Soria, S.

D. Farnesi, A. Barucci, G. C. Righini, S. Berneschi, S. Soria, and G. Nunzi Conti, “Optical Frequency Conversion in Silica-Whispering-Gallery-Mode Microspherical Resonators,” Phys. Rev. Lett. 112(9), 093901 (2014).
[Crossref] [PubMed]

S. Berneschi, D. Farnesi, F. Cosi, G. N. Conti, S. Pelli, G. C. Righini, and S. Soria, “High Q silica microbubble resonators fabricated by arc discharge,” Opt. Lett. 36(17), 3521–3523 (2011).
[Crossref] [PubMed]

Sumetsky, M.

W. Lee, Y. Sun, H. Li, K. Reddy, M. Sumetsky, and X. Fan, “A quasi-droplet optofluidic ring resonator laser using a micro-bubble,” Appl. Phys. Lett. 99(9), 091102 (2011).
[Crossref]

M. Sumetsky, Y. Dulashko, and R. S. Windeler, “Optical microbubble resonator,” Opt. Lett. 35(7), 898–900 (2010).
[Crossref] [PubMed]

Sun, Y.

W. Lee, Y. Sun, H. Li, K. Reddy, M. Sumetsky, and X. Fan, “A quasi-droplet optofluidic ring resonator laser using a micro-bubble,” Appl. Phys. Lett. 99(9), 091102 (2011).
[Crossref]

H. Li, Y. Guo, Y. Sun, K. Reddy, and X. Fan, “Analysis of single nanoparticle detection by using 3-dimensionally confined optofluidic ring resonators,” Opt. Express 18(24), 25081–25088 (2010).
[Crossref] [PubMed]

X. Fan, I. M. White, S. I. Shopova, H. Zhu, J. D. Suter, and Y. Sun, “Sensitive optical biosensors for unlabeled targets: A review,” Anal. Chim. Acta 620(1-2), 8–26 (2008).
[Crossref] [PubMed]

Suter, J. D.

X. Fan, I. M. White, S. I. Shopova, H. Zhu, J. D. Suter, and Y. Sun, “Sensitive optical biosensors for unlabeled targets: A review,” Anal. Chim. Acta 620(1-2), 8–26 (2008).
[Crossref] [PubMed]

Van Blaaderen, A.

T. H. Besseling, J. Jose, and A. Van Blaaderen, “Methods to calibrate and scale axial distances in confocal microscopy as a function of refractive index,” J. Microsc. 257(2), 142–150 (2015).
[Crossref] [PubMed]

Ward, J.

Weise, W.

White, I. M.

X. Fan, I. M. White, S. I. Shopova, H. Zhu, J. D. Suter, and Y. Sun, “Sensitive optical biosensors for unlabeled targets: A review,” Anal. Chim. Acta 620(1-2), 8–26 (2008).
[Crossref] [PubMed]

Wilson, T.

Windeler, R. S.

Wu, X.

Xu, L.

X. Zhang, L. Liu, and L. Xu, “Ultralow sensing limit in optofluidic micro-bottle resonator biosensor by selfreferenced differential-mode detection scheme,” Appl. Phys. Lett. 104(3), 033703 (2014).
[Crossref]

M. Li, X. Wu, L. Liu, and L. Xu, “Kerr parametric oscillations and frequency comb generation from dispersion compensated silica micro-bubble resonators,” Opt. Express 21(14), 16908–16913 (2013).
[PubMed]

Yang, Y.

Y. Yang, J. Ward, and S. N. Chormaic, “Quasi-droplet microbubbles for high resolution sensing applications,” Opt. Express 22(6), 6881–6898 (2014).
[Crossref] [PubMed]

J. Ward, Y. Yang, R. Madugani, and S. N. Chormaic, “Sensing and optomechanics using whispering gallery microbubble resonators,” in Photonics Conference (IPC), (IEEE, 2013), pp. 452–453.
[Crossref]

Zhang, X.

X. Zhang, L. Liu, and L. Xu, “Ultralow sensing limit in optofluidic micro-bottle resonator biosensor by selfreferenced differential-mode detection scheme,” Appl. Phys. Lett. 104(3), 033703 (2014).
[Crossref]

Zhu, H.

X. Fan, I. M. White, S. I. Shopova, H. Zhu, J. D. Suter, and Y. Sun, “Sensitive optical biosensors for unlabeled targets: A review,” Anal. Chim. Acta 620(1-2), 8–26 (2008).
[Crossref] [PubMed]

Zinin, P.

Anal. Chim. Acta (1)

X. Fan, I. M. White, S. I. Shopova, H. Zhu, J. D. Suter, and Y. Sun, “Sensitive optical biosensors for unlabeled targets: A review,” Anal. Chim. Acta 620(1-2), 8–26 (2008).
[Crossref] [PubMed]

Appl. Opt. (2)

Appl. Phys. Lett. (2)

X. Zhang, L. Liu, and L. Xu, “Ultralow sensing limit in optofluidic micro-bottle resonator biosensor by selfreferenced differential-mode detection scheme,” Appl. Phys. Lett. 104(3), 033703 (2014).
[Crossref]

W. Lee, Y. Sun, H. Li, K. Reddy, M. Sumetsky, and X. Fan, “A quasi-droplet optofluidic ring resonator laser using a micro-bubble,” Appl. Phys. Lett. 99(9), 091102 (2011).
[Crossref]

Bioimaging (1)

H. Jacobsen and S. Hell, “Effect of the specimen refractive index on the imaging of a confocal fluorescence microscope employing high aperture oil immersion lenses,” Bioimaging 3(1), 39–47 (1995).
[Crossref]

J. Microsc. (1)

T. H. Besseling, J. Jose, and A. Van Blaaderen, “Methods to calibrate and scale axial distances in confocal microscopy as a function of refractive index,” J. Microsc. 257(2), 142–150 (2015).
[Crossref] [PubMed]

J. Opt. Soc. Am. A (1)

Micron (1)

G. Cox and C. J. R. Sheppard, “Measurement of thin coatings in the confocal microscope,” Micron 32(7), 701–705 (2001).
[Crossref] [PubMed]

Opt. Express (4)

Opt. Lett. (4)

Phys. Rev. Lett. (1)

D. Farnesi, A. Barucci, G. C. Righini, S. Berneschi, S. Soria, and G. Nunzi Conti, “Optical Frequency Conversion in Silica-Whispering-Gallery-Mode Microspherical Resonators,” Phys. Rev. Lett. 112(9), 093901 (2014).
[Crossref] [PubMed]

Other (4)

T. Wilson and C. Sheppard, Theory and Practice of Scanning Optical Microscopy (Academic, 1984).

J. Ward, Y. Yang, R. Madugani, and S. N. Chormaic, “Sensing and optomechanics using whispering gallery microbubble resonators,” in Photonics Conference (IPC), (IEEE, 2013), pp. 452–453.
[Crossref]

M. Born and E. Wolf, Principle of Optics (Cambridge,1999).

J. E. N. Jonkman and E. H. K. Stelzer, “Resolution and contrast in confocal and two-photon microscopy,” in Confocal and Two-photon Microscopy: Foundations, Applications, and Advances, A. Diaspro Ed., Wiley-Liss, Inc., New York (2002).

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Figures (7)

Fig. 1
Fig. 1 Simulated output signal by a confocal microscope from a thin fused silica slab of 10 µm in air (a). Calibration curve obtained by the peaks distance from the simulated signal from fused silica slabs in air with varying thicknesses from 2 µm to 20 µm.
Fig. 2
Fig. 2 Planar section of the z-stack correspondent to the interface of fused silica with air inside the hollow capillary core (a) and orthogonal views along the two axis (b,c). Intensity profile taken along the symmetry axis is shown in (d).
Fig. 3
Fig. 3 Confocal microscope image of a section of fused silica capillary (a) and correspondent intensity profile taken along the yellow line (b).
Fig. 4
Fig. 4 Capillary thickness versus etching time measured through confocal reflectance microscopy along the Z axis (red) and orthogonal XY cut (black).
Fig. 5
Fig. 5 Z-stack images corresponding to the first air to silica interface at the outer shell of the bubble resonator (a) and at 10 µm depth (b). Orthogonal views along the two different axis are represented in (c), (d).
Fig. 6
Fig. 6 Intensity profile along the z-axis at the resonator center.
Fig. 7
Fig. 7 Measured microbubble thickness versus resonator radius. OMBRs were produced from two different capillaries having OD of 140 µm (a) and 240 µm (b). The two lines represent two different approximations. As described above, the cylindrical approximation (blue) gives the upper theoretical limit for the OMBR thickness, whilst the spherical approximation (green) represents the lower limit.

Equations (5)

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a=π r 2 π (rδ) 2 2πrδ
A=π R 2 π (RΔ) 2 2πRΔ
Δ δ = r R
Δ δ = r 2 R 2
d x 2 dz = n 1 n 2 n 2 x 1 R + n 1 n 2 d x 2 dz

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